This invention relates generally to X-ray inspection systems and more particularly to X-ray inspection systems using a multiple focal spot source.
It is known to inspect industrial parts with X-rays, for example using digital radiography (DR) or computed tomography (CT). The X-ray sources used for these methods produce X-rays by accelerating electrons into a dense (generally tungsten) target. The number of X-rays produced is limited primarily by the ability to cool the areas on the target where the electrons strike. Inspection time is directly related to the X-ray output, which is directly related to the focal spot size. However, focal spot size is inversely related to image resolution. Therefore, trade-offs must be made between inspection speed and image quality. Also, X-ray detection devices include linear X-ray detectors, which offer excellent scatter rejection and are well suited for computed tomography. However, because the X-ray beam is collimated into a linear slice, it does not maximize use of the available conical X-ray source yield. This results in increased inspection time and cost.
Accordingly, there is a need for a method and apparatus to improve X-ray source utilization.